Consumption of antidiabetic medicines in Portugal: results of a temporal data analysis of a thirteen-year study (2005-2017).

BACKGROUND

Studies of drug utilization in patients with diabetes, a chronic disease that can be treated with a wide range of available medicines, have attracted substantial social and clinical interest.

OBJECTIVE

To characterize antidiabetic medicine consumption between 2005 and 2017, to evaluate the trends of these medicines in mainland Portugal, and to compare district consumption. An additional objective was to perform a statistical analysis on drug consumption in different regions of Portugal.

METHODS

A descriptive, longitudinal observational study; the setting was mainland Portugal ( excluding Azores and Madeira). Each medicine has a respective defined daily dose (DDD). The sum of the DDD, provides the annual consumption in terms of the DDD for each district each year. When calculating the annual average for the resident district population and the number of days in a year, the denominator is expressed as 1000 inhabitants per day (TID).

MAIN OUTCOME MEASURE

The DDD/TID for mainland Portugal (for all districts) between 2005 and 2017 for antidiabetic medicines. Information was obtained from the official database of prescription medicine invoices with reimbursement in mainland Portugal.

RESULTS

In mainland Portugal, the antidiabetic medicine consumption was 49.3 DDD/TID in 2005 and 88.2 DDD/TID in 2017. The consumption of insulins and their analogs increased from 10.8% to 17.4% compared to the total consumption of antidiabetic medicines. In 2017, the level of biguanide consumption was 23.1 DDD/TID, that of sulphonylurea consumption was 15.8 DDD/TID, that of DPP-4 inhibitor consumption was 6.8 DDD/TID, and that of SGLT2 inhibitor consumption was 3.0 DDD/TID. The oral consumption of fixed-dose combinations reached 21.4 DDD/TID. After employing a geographical division between north and south and between coastal and inland regions, the consumption of several different drugs showed statistically significant differences.

CONCLUSIONS

When comparing 2017 with 2005, the panorama was quite different, with higher levels of consumption of antidiabetic medicines, insulins and their analogs, noninsulin medicines, long-acting and fast-acting insulins and their analogs, metformin, DPP-4 inhibitors and, mainly, metformin combined with a DPP-4 inhibitor. The SGLT2 inhibitors achieved a representative consumption. Different consumption patterns may be related to sociodemographic factors or to clinical practices.